1. Field of the Invention
The present invention relates to an image processing apparatus, an image processing method and a record medium having a program computer-readably recorded therein. In particular, the present invention relates to an image processing apparatus and an image processing method, which are capable of grasping in advance the posture of a taken image, and a record medium having a program computer readably recorded therein.
2. Related Background Art
Up to now, an image processing apparatus such as an electronic camera for recording and reproducing still images and moving images with a memory card having a solid-state memory element as a record medium has already been on the market. An electronic camera provided with an electronic finder, such as a color liquid crystal panel, has also been available on the market.
According to these electronic cameras, it is possible for users of the electronic cameras to continuously display images before taking the images and determine the compositions thereof or to reproduce and display taken images and confirm them. In particular, a function of reproducing taken images immediately after taking the images is highly convenient and is a useful function for users of the electronic cameras.
In addition, another electronic camera is also available which is provided with a posture detecting sensor or the like and distinguishes a posture of the camera to change a range for performing distance measurement and photometry according to the posture of the camera. Japanese Patent Application Laid-open No. 2000-312329 discloses an electronic camera that records postures of the camera together with taken images and rotates the images in accordance with a posture of the camera at the time of image taking to reproduce them.
However, such a conventional image processing apparatus, such as an electronic camera does not have a function for informing a user of the posture judged by the camera. In addition, an electronic camera, which records postures of the camera together with taken images and rotates the images in accordance with the posture of the camera at the time of image taking to reproduce them, does not have a function for informing a user of the direction in which a taken image is rotated and displayed at the time of reproduction.
Therefore, in order to enable a user to judge whether the posture determined by a camera coincides with a posture intended by the user, it is considered desirable to improve the camera such that the camera can display the determined posture.
In addition, in a camera incorporating a strobe or a camera having a strobe externally attached, if irradiation is necessary at the time of forced strobe emission or automatic strobe emission, illumination light irradiates a subject regardless of the vertical position and the horizontal position of the camera.
However, although there is no specific problem when the strobe is positioned above a photographing lens regardless of the posture (vertical and horizontal positions) of the camera at the time of image taking, an unnatural shadow is projected on a subject if illumination light irradiates the subject when the strobe is positioned under the photographing lens. For example, as shown in FIG. 20, if there is a wall 302 behind a subject 301, a shadow 303 of the subject 301 is unnaturally projected on the wall 302 behind the subject 301.
In addition, as described in Japanese Patent Application Laid-open No. 11-024150, if a gravity sensor is used as a posture detecting sensor, it is likely that the gravity sensor cannot perform correct posture detection if the elevation angle is equal to or larger than a predetermined angle (e.g., 70 degrees) in such a case where image taking is performed with a photographing lens oriented upward. Thus, an elevation angle sensor is provided in a camera to turn off the gravity sensor when the elevation angle is equal to or larger than the predetermined angle. In this case, positional information of the camera at the time of image taking cannot be recorded in images after taking the images. In addition, the camera does not have a function of informing a user that the camera is in an undetectable state at the time of image taking.
Therefore, if it is likely that a shadow of a subject is unnaturally projected at the time of image taking, it is considered desirable to improve a camera such that the camera can inform a user to that effect in advance. In addition, if a posture of the camera is undetectable, it is considered desirable to improve the camera such that the camera can inform a user to that effect.